1. Field of the Invention
This invention relates to a video tape recorder/reproducer which has instant replay. It is capable of recording standard NTSC color or monochrome video signals and then immediately replaying the recorded material either forward or in reverse, at normal speeds, twice normal speeds, one-half normal speeds, one-fifth normal speed, at continuously variable speeds ranging from stop-action to normal.
More specifically, it relates to a video signal recording and/or reproducing device in which a tape-like recording medium is intermittently transported in its longitudinal direction to form record tracks spaced by a predetermined length from each other on the recording medium.
2. Description of the Prior Art
A VTR (Video Tape Recorder) is known in which a magnetic tape is intermittently transported, and video signal of one field or one frame is recorded on, or reproduced from, the magnetic tape during the stop of the latter. In such a VTR, no guard band noise occurs on the reproduced picture in the slow reproduction mode, the still reproduction mode and reverse reproduction mode in which the transport speeds of the magnetic tape or the transport directions thereof are different. Accordingly, a reproduced picture of high quality can be obtained in the VTR.
However, a control signal (hereinafter called "CTL signal") as a reference signal for servo-control of a head of a rotary head drum or servo-control of a capstan of a tape drive system is recorded on the marginal portion of the magnetic tape which is moving. Because the CTL signal cannot be recorded on, and reproduced from, the magnetic tape unless the magnetic tape moves relative to a CTL head for recording/reproducing the CTL signal.
In some of the conventional VTRs, a portion of a magnetic tape wrapped on a rotary head drum is intermittently transported, while another portion of the magnetic tape is transported at a constant speed. However, in this case, a tape drive system is complicated in construction. Further, the relative position between the above described two portions, namely the relative position between the record track on the magnetic tape and the recorded CTL signal, is apt to vary. There is a problem that the tracking of the head cannot be accurately controlled in the reproducing mode. Further, such a VTR is known that, while the magnetic tape is moving the CTL signal is recorded on the magnetic tape to be intermittently transported. However, in this case, since the magnetic tape is intermittently driven by the capstan, the running speed of the magnetic tape rapidly increases and rapidly decreases. Accordingly, some slip sometimes occurs between the magnetic tape and the capstan. For the reason, the CTL signals cannot be sometimes accurately recorded at the regular intervals on the magnetic tape, and mistracking of the head occurs in the reproducing mode.